A multicentre, randomised, open-label, parallel-group Phase 2b study of belotecan versus topotecan for recurrent ovarian cancer

Background: This Phase 2b study compared the efficacy and toxicity of belotecan and topotecan in recurrent ovarian cancer. Methods: Patients with platinum-sensitive recurrent or platinum-resistant recurrent ovarian cancer (PRROC) were randomised 1:1 to receive belotecan 0.5 mg/m² or topotecan 1.5 mg/m² for five consecutive days every 3 weeks. The primary endpoint was overall response rate (ORR); secondary endpoints were progression-free survival (PFS), overall survival (OS), and toxicity. Results: A total of 140 (belotecan, n = 71; topotecan, n = 69) and 130 patients (belotecan, n = 66; topotecan, n = 64) were included in the intention-to-treat (ITT) and per-protocol (PP) populations. ORR did not differ significantly between the belotecan and topotecan groups (ITT, 29.6% versus 26.1%; PP, 30.3% versus 25%). Although PFS did not differ between the groups, belotecan was associated with improved OS compared with topotecan in the PP population (39.7 versus 26.6 months; P = 0.034). In particular, belotecan showed longer OS in PRROC and non-high-grade serous carcinoma (non-HGSC; PP, adjusted hazard ratios, 0.499 and 0.187; 95% confidence intervals 0.255–0.977 and 0.039–0.895). Furthermore, there were no differences in toxicities between the two groups. Conclusions: Belotecan was not inferior to topotecan in terms of overall response for recurrent ovarian cancer. Clinical trial registration: NCT01630018.